Mineral oil compositions and method of making same



tures the reaction is somewhat slower and the at 130 F.', and a pour test (in the untreated conwax-phenol becomes more viscous and in such dition), of 20 F. In theflrst horizontal line is cases it is desirable to use a suitable inert diluent shown the difierent percentages of depressant or solvent such for example as ethylene chloadded to the oil. In the second horizontal line is 5 ride, to reduce the viscosity of the reaction mixshown the pour-point of the oil without any de- 5 ture and to cut down'its tendency to foam. At pressant. In the third horizontal line is shown 300 F. the time required to complete the reacthe different pour points of the oil containing tion depends upon the time required for the ad- 'diiferent percentages of a well known depressant dition of the acid chloride to the mixture, the latdesignated "naphthalene depressant" which is ter being limited only by the foaming produced prepared by combining chlorwax and naphtha- 10 by the evolution of hydrogen chloride gas. After lene according to well-known prior methods. esteriflcation, the product is purified to free it of Similarly the fourth horizontal line shows the aluminum chloride since we have discovered that pour points obtained after the addition to the V residual aluminum chloride tends to impair the oil of different percentages of a depressant prel stability of thedepressant. The product may be paredby combining-chlorwax and phenol, while conveniently purified by a process of water-washthe fifth line shows in the same mannerthe pour ing. The washing with water alone is difllcult points obtained after the addition to the oil of because of. the great tendency of the product to different percentages of the improved pour point emulsify, but it has been found that if there is depressant oi' the present invention, which is desadmixed with the water an alcohol, such as ignated in this table as phthalatedepressant. 20

- Table I U A. S. T. M. pour points of lubricating oil containing various percentages of added depressants 25.

Percent depressant 0% I am am. 5% 54% m. 1%

Oil alone 7 +20 F. I

I Naphthalene depress +l0 F. 0 F. 15 F. .20 F- 30 Wax-phenoldepressant +5 F. -l0 F. 25 F. -25 F. I

Phthalate depressant --l0 F. 20 F. 20 F. 25 F. -25 F.

butanol, and the product washed preferably From the above table, it is evident that the 5 about a half dozen times with equal volumes of novel depressant herein disclosed is a vastly more water, each volume of water containing about 2% effective depressant P ularly at percenta butanol, the aluminum chloride, chlorine etc., are below about 4% than either the naphthalene substantially completely removed. The washing pour point depressant, widely known and used in should be carried out with vigorous stirring and the art, or the wax phenol depressant which is v 40 at relatively high temperatures, preferably at much more effective than the former. For in- 0 about 175 F. Also the washing should be constance the phthalate depressant is evidently tinued until the productpreferably contains an about sixteen times as eflective asthe naphthaamount of aluminum correspondingto not more lene depressant in attaining pour points of about than about 0.02% of aluminum chloride. 20 F., since a pour of 20 F. which re- The following example of the preferred method quires 1% of the naphthalene depressant may 5 of this invention illustrates more particularly the be attained by of 1% of the phthalate depress-, specific proportions which we prefer to use: 800 ant. I

parts by weight of chlorwax, containing 14% of The heat stability characteristics of this imchlorine, and 74 parts by weight of phenol are proved depressant is illustrated by the data pre- 60 melted together and heated to a temperature of sented in Table II. In obtaining this data, the 150 F. To this hot mixture is then added 24 above-mentioned oil, vlz., lubricant oil of 249" partsby weight of aluminum chloride. The mix- Saybolt at 130 F. containing different percentture is then heated to 250 F. and then slowly to ages of the different depressants was subjected 350 F. After the evolution of hydrochloric gas to a heating test which has been found to quite has ceased the reaction mixture is then cooled to closely. simulate service conditions in an auto- 55 300 F. and 80 parts by weight by phthalyl chlomobile crankcase. This test, which is herein reride gradually'added, the rate of addition being ferred to as the SOS test is accomplished by governed by the degree of foam formation resultmaintaining a 300 cc. sample of the oil at a closeing from the evolution of hydrochloric acid gas. ly controlled temperature of 342 F. in a glass After the acid chloride is completely incorporatbeaker; the oil being continuously agitated with a 60 ed in the mixture, it is then allowed to cool to motor-driven steel propeller. Samples are withabout 175 F., washed six times with an equal drawn at the expiration of three days and four volume of water containing 2% of butanol, using days respectively for examination. A very cona fresh portion of water and alcohol for each siderable number of experiments have shown that washing- As a result of these operations, there is two days of this heat test are about equivalent to 65 obtained somewhat in excess of 800 parts by 2,000 miles of normal service in the lubrication weight of the phthalic ester of tetrawax-substiof, an automobile gasoline engine. The-effeq of tuted-phenol which constitutes the preferred this heat test upon the pour points of the oil-- form of our novel pour point depressant. containing diflerent percentages of wax phenol The extraordinary effectiveness of our imdepressant and also upon the same 011 contain- 70 proved pour point depressant is illustrated by the ing diiferent percentages of the phthalate depressdata shown in the following table. In obtaining ant of the present invention is illustrated by the this data the depressants were admixed, in the data shown in Table II in which the nature of indicated proportions, with a petroleum lubricant thedepressant is shown in vertical column I, .the

7 oil having a Saybolt universal viscosity of 2492 percentages of the different depressants in vertical column II, the initial pour points in vertical column III, and the. pour points after three days and four days in vertical columns IV and V respectively.

From this table it will be observed that the improved depressant of the present invention even in concentrations as low as of 1% retains sufflcient eiliciency, after exposure to conditions equivalent to 3,000 miles of normal driving service, to depress the pour point of the oil to a tempera- .ture well below any atmospheric temperature normally encountered in service, and that in somewhat greater concentrations it suifered' practically no deterioration at all after exposure to these conditions.

The heat stability of this improved depressant under conditions closely approximating actual service conditions is illustrated by the data shown in the following Table III. In obtaining this data Table III Degrees Fahrenheit Pour point of oil without depressant +20 Pour point of oil containing phthalate depressant before test -20 Pour point of oil containing phthala'te depressant after 72 hours dynamometer test -20 In addition to heat stability, it is likewise desirable, as previously mentioned, that a useful depressant to be stable against hydrolysis, since an automobile crankcase, especially in winter, practically always contains some water produced by condensation of'watcr vapor. The improved pour point depressant herein disclosed possesses a remarkably high resistance to hydrolysis, and

is quite stable toward hydrolytic deterioration as was determined by subjecting the above-mentioned 011 containing 1 5 of 1% of the depressant to reflux distillation with water for five days, after which the oil was found to have suifered no rise in pour point. 0f further importance in this connection is the fact that if hydrolysis 'did occur to avery limited extent under extreme conditions it would be necessary only to increase the amount of depressant used by a very small fraction of 1% to still have more depressant efficiency than is necessary even under inordinately prolonged service under extreme conditions. Furthermore we have found that the possible products of hydrolysis have very little tendency to corrode the metals used in automotive equipment under normal conditions so that our improved depressant does not corrode such metals to any substantial extent even when used in the presence of such moisture. While we do not wish to limit our invention to any specific explanation or theory as to the exact composition or molecular structure of the preferred form of our improved depressant, nevertheless, we believe it to be composed predominantly of a compound which corresponds substantially to the following general formula:

R R OH wherein four of the R's and foul of the R-s are alkyl radicals corresponding to those which characterize petroleum wax, the remaining R's and R"s being hydrogen.

Our improved depressant may therefore be properly designated as a di-tetra-wax-phenylphthalate or in a. more generic sense as a di-tetraallgvl-phenyl-phthalate wherein the alkyl corresponds to an aliphatic hydrocarbon of relatively high .molecular weight such as characterize the heavier petroleum fractions comprised within the range which includes petrolatum and the crystallin petroleum waxes.

We claim:

'1. A mineral oil comprising a mixture of liquid oils and waxy hydrocarbons, and having incorporated therein a relatively small proportion of the phthalic ester of a heavy alkyl substituted phenol, said ester being capable of depressing the pour point of the oil.

2. A mineral oil comprising liquid oils and waxy hydrocarbons and having incorporated therein a relatively small proportion of the product produced by chemically condensing together phenol and chlorinated wax and thereafter esterlfying the condensation product thus obtained with a substance selected from the group consisting of phtlialyl chloride and phthalic anlrvdride, said ester having the property of depressing the pour point of the oil. 7

3. A mineral lubricant oil composition of low pour point comprising a lubricant oil of high pour point and in admixture therewith a small proportion of a product produced by chemically condensing phenol and chlorinated wax in the presence of aluminum chloride as catalyst, and thereafter reacting the product thus obtained with phthalyl chloride without removal of the aluminum chloride catalyst and separating the aluminum chloride from the reaction product, said reaction product having the property of depressing the pour point of the oil.

4. A mineral oil composition comprising a mixture of liquid oils and waxy hydrocarbons. and in admixture therewith a small proportion of the reaction product produced by chemically reacting one equivalent amount of phenol with suificient chlorinated wax, containing 14% of chlorine, to provide four equivalents of chlorine, heating the mixture to about 150 F.. adding aces mixture to about 300 F., adding one equivalent of phthalyl chloride, and after the addition of the phthalylchloride cooling and water-washing the reaction product to remove aluminum chlm ride, the reaction product thus obtained having the ability to depress the pour point of the said mixture of liquid oils and waxy hydrocarbons.

5. The method of making a hydrocarbon lubricant oil of low pour point which comprises the following steps: Chemically reacting chlorwax and phenol by means of anhydrous aluminum chloride as catalyst, the reaction being initiated at a temperature of about 150 E, and slowly heating the reactants to about 350 F., the chitinwax containing around 14% of chlorine, the proportions of the ingredients being such that about four equivalents of chlorine are present for each equivalent of phenol and such that there is present an amount of aluminum chloride corresponding to about 3% of the chlorwax, cooling the reactants to a temperature of about 200 E, adding tothe reaction mixture one equivalent of phthalyl chloride to esterify the phenol product .thus obtained, washing the reaction product to remove substantially all aluminum chloride, and adding a relatively small amount of the finished reaction product thus obtained to a mineral IU- drocarbon oil of initially high pour point.

6. The method '01 making a hydrocarbon lubricant oil of low pour point which comprises the following steps: Chemically reacting chlorwax and phenol in the presence of anhydrous aluminum chloride as catalyst, initiating the reaction at about 150 F., and slowly heating the reamants to about 350 F., the chlorwax containing around 14% of chlorine, the proportions of the ingredients being such that around four equivalents of chlorine are initiallypresent for each equivalent of phenol and such that there is present in the reaction mixture an amount of aluminum chloride corresponding to about 3% by weight of the chlorwax, cooling the reaction mixture to a temperature of about 300 F., adding to the reaction mixture one equivalent of phthalyl chloride to esterify the phenol product thus obtained, washing the reaction product to remove substantially all aluminum chloride, and adding a relatively small amount of the finished reaction product thus obtained to a mineral hydrocarbon oil of initially high pour point.

7. The method of making a hydrocarbon lubricant oil of low po r point which comprises the following steps: Chemically reacting chlorwax and phenol in the presence of anhydrous aluminum chloride as catalyst, initiating the reaction at about 150 F., and slowly heating the reaction mixture to about 350? the chlorwax containing-around 14%"of chlorine, the proportions of the ingredients being such that about four equivalents of chlorine are initially present for each equivalent of phenol and such that there is present in the reaction mixture an amount of aluminum chloride corresponding to, about 3% by weight of the chlorwax, cooling the mixture to a temperature of 200 F., adding to the maction mixture one equivalent ofv phthalyl chloride to esteriiy the phenolic compound thus obtained,

washing the reaction mixture with water con taining a small amount of butanol, to remove aluminum chloride, and adding a small amount of the finished reaction product thus obtained to a mineral hydrocarbon oil of initially high pour point. l

8. A mineral oil comprising a mixture of liquid oils and waxy hydrocarbons, and having incor- 5 porated therein a small proportion, not more than 1%, of the 'phthalicester of a heavy alkylsub stituted phenol, said ester being capable of depressing the pour point of the oil.

9. A mineral lubricant oil composition of low pour point comprising a lubricant oil of high pour point and inadmixture therewith a small proportion, not more than 1%, of a product produced by chemically condensing phenol and chlorinated wax in the presence of aluminum chloride as catalyst, and thereafter reacting the product thus obtained with phthalyl chloride without removal of aluminum chloride,purlfying the reaction product by separating the aluminum chloride therefrom, saidreaction product '20 having the property of depressing the pour point of the oil.

10. A mineral oil composition comprising a of liquid oil and waxy hydrocarbons and in therewith a small proportion of 25 where-inst least four of the R's and four of the R"s are heavy alkyl radicals corresponding to those which characterize petroleum wax, said added compound having the power of depressing 7o pour point-of the said mixture of oil and fury hydrocarbons.

ORLAND M. REIFF. DARWIN E. BADERTSCHER. 15

n or

July21, 1936. I G E M 2,048,467

GRINDING MACHINE Filed Nov. 5, 1934 '6 Sheets-Sheet 1 INVENTOR.

IZ' 'P f j ATTORNEY. 

